diff options
| -rw-r--r-- | tools/go_marshal/gomarshal/generator_interfaces.go | 2 | ||||
| -rw-r--r-- | tools/go_marshal/gomarshal/generator_tests.go | 15 | ||||
| -rw-r--r-- | tools/go_marshal/marshal/marshal.go | 4 |
3 files changed, 20 insertions, 1 deletions
diff --git a/tools/go_marshal/gomarshal/generator_interfaces.go b/tools/go_marshal/gomarshal/generator_interfaces.go index 22aae0f6b..3aa299ccd 100644 --- a/tools/go_marshal/gomarshal/generator_interfaces.go +++ b/tools/go_marshal/gomarshal/generator_interfaces.go @@ -301,7 +301,7 @@ func (g *interfaceGenerator) emitMarshallable() { primitiveSize += size } else { g.recordUsedMarshallable(t.Name) - dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("%s.SizeBytes()", g.fieldAccessor(n))) + dynamicSizeTerms = append(dynamicSizeTerms, fmt.Sprintf("(*%s)(nil).SizeBytes()", t.Name)) } }, selector: func(n, tX, tSel *ast.Ident) { diff --git a/tools/go_marshal/gomarshal/generator_tests.go b/tools/go_marshal/gomarshal/generator_tests.go index 5ad97af14..8c28b00d0 100644 --- a/tools/go_marshal/gomarshal/generator_tests.go +++ b/tools/go_marshal/gomarshal/generator_tests.go @@ -167,11 +167,26 @@ func (g *testGenerator) emitTestWriteToUnmarshalPreservesData() { }) } +func (g *testGenerator) emitTestSizeBytesOnTypedNilPtr() { + g.inTestFunction("TestSizeBytesOnTypedNilPtr", func() { + g.emit("var x %s\n", g.typeName()) + g.emit("sizeFromConcrete := x.SizeBytes()\n") + g.emit("sizeFromTypedNilPtr := (*%s)(nil).SizeBytes()\n\n", g.typeName()) + + g.emit("if sizeFromTypedNilPtr != sizeFromConcrete {\n") + g.inIndent(func() { + g.emit("t.Fatalf(\"SizeBytes() on typed nil pointer (%v) doesn't match size returned by a concrete object (%v).\\n\", sizeFromTypedNilPtr, sizeFromConcrete)") + }) + g.emit("}\n") + }) +} + func (g *testGenerator) emitTests() { g.emitTestNonZeroSize() g.emitTestSuspectAlignment() g.emitTestMarshalUnmarshalPreservesData() g.emitTestWriteToUnmarshalPreservesData() + g.emitTestSizeBytesOnTypedNilPtr() } func (g *testGenerator) write(out io.Writer) error { diff --git a/tools/go_marshal/marshal/marshal.go b/tools/go_marshal/marshal/marshal.go index e521b50bd..20353850d 100644 --- a/tools/go_marshal/marshal/marshal.go +++ b/tools/go_marshal/marshal/marshal.go @@ -48,6 +48,10 @@ type Marshallable interface { // SizeBytes is the size of the memory representation of a type in // marshalled form. + // + // SizeBytes must handle a nil receiver. Practically, this means SizeBytes + // cannot deference any fields on the object implementing it (but will + // likely make use of the type of these fields). SizeBytes() int // MarshalBytes serializes a copy of a type to dst. dst must be at least |